My parents say that when I was a toddler I was already interested in radio. I don't remember that, but I remember building my first real radio receiver, from a kit, at age eight. It was a primitive crystal set. It received one station very well, but I didn't know how to make it selective, so that it could "tune in" other stations. By age ten, however, I'd built a much better receiver, also from a kit, that was not only very sensitive (so it could hear relatively weak, faraway stations) but also highly selective (so I could hear the station I wanted without also hearing other stations). From that time (51 years ago) until the present, I have always been sleepy. I am always staying up too late listening to some radio.

I learned the Morse code around my seventh birthday, from a comic-book biography of its inventor, Samuel F. B. Morse. I noticed that Mr. Morse and I shared a birthday, April 27th, and also that he had built the first significant electric telegraph line from Baltimore, MD, where I was born and was living and attending school, to Washington, DC. Ten years later when I came as a college freshman to M.I.T. in Cambridge, MA, I learned that Mr. Morse had been born in Charlestown, which is next to Cambridge and not far from Belmont.

By age twelve I'd built several radios, and my display of radio circuits won a prize at the Baltimore Science Fair. Recently my mother sent me this old newspaper clipping:

At age 13 I got my first, Novice Class, amateur radio license. To get a Novice license in those days you had to pass tests of sending and receiving Morse code accurately at a speed of five words per minute. A Novice Class license expired after one year and could not be renewed. To continue in amateur radio you had to qualify for a higher-class license. Before my Novice year ended, I got a General Class license, which required sending and receiving Morse code at 13 words per minute. Some years later I got an Extra Class license, which required sending and receiving Morse at 20 words per minute.

Nowadays, the Morse-code requirements for amateur radio licenses range from zero to not much -- which is nice for people who are interested in radio but who think that learning Morse code will be too hard. Actually it's easy; and it's especially easy for kids. It's a shame that, now, many hams don't know Morse code well enough to use it on the air. Morse code is much more effective than voice for communicating across great distances and for penetrating noise and interference. For its signal to be understandable, a voice transmitter requires about 25 times more power than a Morse-code transmitter!

Ham radio led me directly to a professional career in radio science and engineering. I mentioned that I went to M.I.T. After finishing college and graduate school at M.I.T., I became member of the faculty there. Both my teaching and my research work have always related to radio. I've done radio astronomy and radar astronomy -- measuring and mapping the moon and planets, stars, galaxies, and quasars by radio -- and my specialty is using radio to determine the positions and motions of faraway things with super-super-accuracy.